Markéta Kuklová

The level of serum visfatin (PBEF) is associated with total number of B cells in patients with rheumatoid arthritis and decreases following B cell depletion therapy.

OBJECTIVE Visfatin, also known as pre-B cell colony-enhancing factor, was recently characterized as a potent pro-inflammatory mediator in rheumatoid arthritis (RA). The aim of this study was to determine the effect of B cell depletion with rituximab on serum visfatin levels in patients with active RA. METHODS We evaluated 31 patients with RA starting rituximab therapy at baseline and after 16 and 24 weeks using disease activity score (DAS28). The control group consisted of 33 gender and age-matched healthy individuals. CD19(+) B cells were assessed by flow cytometry and serum levels of visfatin and B cell-activating factor of the TNF family (BAFF) were measured by ELISA at baseline and week 16. RESULTS Total number of B cells correlated positively with serum visfatin levels (rs=0.417, P=0.025) and negatively with serum BAFF levels (rs=-0.486, P=0.008) at baseline. Serum visfatin levels were significantly higher in patients with RA compared with healthy controls (P=0.026), and significantly decreased (P=0.010), while BAFF increased (P<0.001), and both proteins became negatively correlated following treatment with rituximab (rs=-0.438, P=0.017). Visfatin levels did not correlate with the disease activity, but lack of change in the serum visfatin levels between baseline and week 16 predicted worsening disease activity between weeks 16 and 24 (rs=0.452, P=0.014). CONCLUSION In patients with active RA, serum visfatin levels are related to the number of B cells rather than to disease activity and decrease in response to treatment with rituximab. Further studies are necessary to show if visfatin is a marker with predictive value for deterioration of RA.

Adiponectin relation to skin changes and dyslipidemia in systemic sclerosis

OBJECTIVES Adiponectin was initially described as a regulator of metabolic homeostases. Further studies demonstrated its involvement in the regulation of inflammatory diseases, particularly rheumatic and vascular diseases and some fibrotic processes. The aim of this study was to evaluate adiponectin in the circulation of patients with systemic sclerosis (SSc) and characterise its potential association with skin changes and SSc-related features. METHODS Serum levels of adiponectin, interleukin-6 and soluble receptor for interleukin-2 (by ELISA), lipid levels, CRP (by turbidimetry), ANA (by immunofluorescence), autoantibodies of the ENA complex (by immunoblot) and urine levels of pyridinoline and deoxypyridinoline (by HPLC) were measured in 39 patients with SSc, and adiponectin levels were determined in 30 healthy controls matched by age, sex, and body mass index (BMI). Organ manifestations were recorded and skin changes were assessed using the modified Rodnan skin score. RESULTS Adiponectin serum levels were similar between patients with SSc and healthy controls (median (IQR), 6.9 (5.9-9.1) vs. 7.8 (6.2-9.5)μg/ml, p=0.670). Levels of serum (ln) adiponectin were negatively correlated with the skin score (r=-0.379, p=0.017). Regression analysis of the relationship between adiponectin and markers of interest provided two statistically significant models: A- with explanatory variables HDL-cholesterol, skin score, disease duration, age (R(2)=0.580); and B- with CRP, skin score, age (R(2)=0.550); in order of a decreasing influence. CONCLUSION Based on the results of this study, it might be speculated that adiponectin plays a protective role in skin- and atherosclerosis-related changes during SSc.

Progranulin Is Associated with Disease Activity in Patients with Rheumatoid Arthritis

Objective. Progranulin (PGRN) is implicated in the pathogenesis of rheumatoid arthritis (RA). The aim of this study was to assess the relationship between PGRN and disease activity in RA. Methods. PGRN levels were evaluated in patients with RA (n = 47) and OA (n = 42) and healthy controls (n = 41). Immunohistochemical analysis of PGRN in synovial tissues was performed. The association between PGRN and C-reactive protein (CRP), disease activity score (DAS28-CRP), and health assessment questionnaire (HAQ) was studied. Results. Circulating PGRN was elevated in patients with RA and OA compared to healthy controls (227.1 ± 100.2 and 221.5 ± 102.5 versus 128.1 ± 34.7 ng/mL; P < 0.001). Synovial fluid levels of PGRN were higher in patients with RA compared to OA (384.5 ± 275.3 versus 241.4 ± 165.2 ng/mL; P = 0.002). PGRN expression was significantly upregulated in the synovial tissue of RA patients particularly in the inflammatory infiltrates. Serum PGRN levels correlated with DAS28 (r = 0.327, P = 0.049) and HAQ score (r = 0.323, P = 0.032), while synovial fluid PGRN correlated only with HAQ (r = 0.310, P = 0.043) in patients with RA. PGRN levels were not associated with CRP or autoantibodies. Conclusions. This study demonstrates increased PGRN expression at local sites of inflammation and association between PGRN levels, disease activity, and functional impairment in patients with RA.

Decreased circulating visfatin is associated with improved disease activity in early rheumatoid arthritis: data from the PERAC cohort.

Objective To evaluate circulating visfatin and its relationship with disease activity and serum lipids in patients with early, treatment-naïve rheumatoid arthritis (RA). Methods Serum visfatin was measured in 40 patients with early RA before and after three months of treatment and in 30 age- and sex-matched healthy individuals. Disease activity was assessed using the Disease Activity Score for 28 joints (DAS28) at baseline and at three and 12 months. Multivariate linear regression analysis was performed to evaluate whether improved disease activity is related to serum visfatin or a change in visfatin level. Results Serum visfatin was significantly elevated in early RA patients compared to healthy controls (1.92±1.17 vs. 1.36±0.93 ng/ml; p = 0.034) and significantly decreased after three months of treatment (to 0.99±0.67 ng/ml; p<0.001). Circulating visfatin and a change in visfatin level correlated with disease activity and improved disease activity over time, respectively. A decrease in visfatin after three months predicted a DAS28 improvement after 12 months. In addition, decreased serum visfatin was not associated with an improved atherogenic index but was associated with an increase in total cholesterol level. Conclusion A short-term decrease in circulating visfatin may represent an independent predictor of long-term disease activity improvement in patients with early RA.

Adipokine profile is modulated in subcutaneous adipose tissue by TNFα inhibitors in patients with rheumatoid arthritis

A protective effect of obesity showing that increased adiposity protects against radiographic joint damage in patients with rheumatoid arthritis (RA) has been reported.1 2 Recently, adipokines were suggested as a molecular link explaining this paradoxical association.3,–,5 The levels of serum adiponectin and visfatin have been shown to be associated with increased, radiographic joint damage in RA, while leptin is associated with reduced radiographic joint damage.4 5 Therefore, we tested whether tumour necrosis factor α (TNFα) inhibitor therapy, which prevents joint damage in majority of patients with RA, may be associated with a change in the local production of adipokines in subcutaneous adipose tissue (SAT). SAT samples were obtained from the same abdominal region by aspiration with a bioptic needle in nine patients with RA prior to and 6 months after the treatment with etanercept. Adipose tissue samples were …

The level of fatty acid-binding protein 4, a novel adipokine, is increased in rheumatoid arthritis and correlates with serum cholesterol levels

OBJECTIVE To assess the expression of the novel adipokine Fatty Acid Binding Protein-4 (FABP4) in synovial tissues, serum and the synovial fluid of patients with rheumatoid arthritis (RA) and osteoarthritis (OA) and to study the relationships among FABP4, disease activity and metabolic status. METHODS FABP4 levels were measured in the serum and synovial fluid of 40 patients with RA and 40 control patients with OA. The disease activity score (DAS28), C-reactive protein (CRP) levels and serum lipids were assessed in patients with RA. Immunohistochemical analysis and confocal microscopy were used to study the expression and cell-specific distribution of FABP4 in synovial tissues. RESULTS The age, sex and body mass index (BMI) adjusted levels of FABP4 were significantly higher in the serum (p=0.001) and synovial fluid (p=0.005) of patients with RA when compared to OA patients. FABP4 levels were higher in females than in males and correlated positively with body mass index (BMI) in patients with RA. Independent of confounders, FABP4 levels correlated with total cholesterol and LDL cholesterol in patients with RA, but not in OA patients. FABP4 levels were not affected by disease activity. Furthermore, the increased expression of FABP4 that was otherwise restricted to synovial fibroblasts, macrophages and B-cells was noted in RA patients at levels higher than that observed in OA patients. CONCLUSIONS The observed elevation of FABP4 levels in RA patients and the positive correlation of the adipokine to cholesterol suggest that FABP4 may represent a potential link between RA and the increased risk of atherosclerotic changes.

THU0528 Decrease in Circulating Visfatin Levels is Associated with Disease Activity Improvement in Early Rheumatoid Arthritis

Background Identification of novel molecules contributes to better understanding of rheumatoid arthritis (RA) pathogenesis and offers promise for comprehensive identification of novel biomarkers that would allow monitoring of disease activity and individualize prognosis of RA patients. Visfatin may represent a novel biomarker of disease severity. Serum visfatin levels are elevated in RA, may be associated with the degree of inflammation, clinical disease activity and radiographic joint damage. Objectives To assess circulating visfatin and its relationship with disease activity and serum lipids in patients with early treatment-naïve RA and to evaluate the effect of treatment with conventional synthetic DMARDs on visfatin levels. Methods Serum levels of visfatin were analysed in 40 patients with early RA before and after three months of treatment and in 30 age- and sex-matched healthy individuals. Disease activity was assessed by the Disease Activity Score for 28 joints (DAS28) at baseline and at months 3 and 12. Multivariate linear regression analysis was performed to evaluate whether disease activity improvement can be related to serum circulating visfatin or to a change of visfatin levels. Results Visfatin serum levels were significantly elevated in early RA patients compared with healthy controls (1.92±1.17 vs. 1.36±0.93 ng/ml; p=0.034) and significantly decreased after three months of treatment (to 0.99±0.67 ng/ml; p<0.001). Circulating visfatin and change in visfatin levels correlated with disease activity and disease activity improvement over time, respectively. Visfatin decrease after three months predicted DAS28 improvement after 12 months (p=0.031, adjusted R2=10.1%). In addition, decrease of serum visfatin levels was not associated with improved atherogenic index, but was negatively associated with the increase of total cholesterol levels. Conclusions Short-term decrease in circulating visfatin levels may represent independent predictor of long-term disease activity improvement in patients with early RA. Acknowledgements This study was supported by Internal Grant Agency of Ministry of Health of the Czech Republic NT/13696-4 and Research Project No. 00023728. Disclosure of Interest : None declared DOI 10.1136/annrheumdis-2014-eular.4092

Modulation of subcutaneous adipose tissue adipokines by TNF-α blockade therapy in patients with inflammatory arthritides

Objective Increased adiposity has been recently shown to protect against radiographic progression in rheumatoid arthritis (RA). Moreover, low adiponectin serum levels were suggested as mechanistic link between high adiposity and decreased radiographic damage in RA. Therefore, the aim of this study was to examine the hypothesis that beneficial effect of tumour necrosis factor (TNF)-α blockade therapy may be associated with local changes of adipokines in subcutaneous adipose tissue. Methods Samples of subcutaneous adipose tissue for protein analysis were obtained from the same abdominal region in patients with RA (n=9) and ankylosing spondylitis (n=4) prior to and 6 months after the commencement of etanercept. Commercial ELISA assays were used for detection of subcutaneous adipose tissue concentrations of TNF-α, interleukin (IL)-1, IL-6 and adipokines leptin, adiponectin, resistin, visfatin, vaspin and omentin. Western blotting was used to confirm modulated levels of the protein(s). Results Subcutaneous adipose tissue concentrations of IL-1, TNF-α, leptin, resistin, visfatin, vaspin and omentin have not changed during the observation period. However, the levels of adiponectin and IL-6 decreased significantly 6 months following initiation of etanercept therapy (from 35.65±16.45 μg/ml to 15.70±10.40 μg/ml (p=0.003) and from 102.36±45.26 pg/ml to 79.66±31.92 (p=0.049), respectively). This observation was confirmed by western blotting. None of the cytokines or adipokines was associated with serum C-reactive protein. Conclusion Beneficial effect of TNF-α blockade therapy on structural joint damage in patients with inflammatory arthritides may be, at least in part, mediated through the decrease of subcutaneous adipose tissue adiponectin and IL-6.

Potential role of S100A4 in an immune response of rheumatoid arthritis

Background Rheumatoid arthritis (RA) is characterised by systemic and local inflammation caused by enhanced activity of immune cells producing several inflammatory mediators. S100A4 is a protein with metastasis-promoting functions that is significantly upregulated in RA, induces expression of matrix degrading enzymes and regulates apoptosis of synovial fibroblasts. Therefore, the aim of the present study was to investigate the role of S100A4 in an immune response. Methods Peripheral blood mononuclear cells (PBMC) were isolated from patients with RA. CD14 and CD3 cells were selected from PBMC using microbeads. To investigate extracellular functions, S100A4, S100A8 and S100A12 proteins (1 μg/ml) were used for in vitro experiments. The protein levels of tumour necrosis factor (TNF)-α, interleukin (IL)-1 and IL-6 were assessed using ELISA. Receptor involvement was investigated using antibodies against RAGE, Toll-like receptor (TLR)-4, TLR-2 and inhibitor of MyD88. To determine intracellular signalling pathways, inhibitors of NFκB, p38, ERK1/ERK2 and JNK were used. Results S100A4 significantly upregulated expression and production of TNFα, IL-1 and IL-6 in PBMC compared to unstimulated cells (p<0.001). Importantly, production of these cytokines was markedly enhanced in response to S100A4 compared to S100A8 or S100A9. In addition, S100A4 upregulated TNFα, IL-1 and IL-6 in both CD14 and CD3 cells (p<0.005). Furthermore, S100A4 induced secretion of these cytokines was significantly blocked by NFκB inhibitor (p<0.01), MyD88 inhibitor (p<0.02) and antibody against TLR-4 (p<0.02), but not by antibodies against RAGE or TLR-2. Blockade of MAP-kinase p38 inhibited most significantly synthesis of TNF-α. Conclusion This is the first study to demonstrate S100A4 as a potent proinflammatory mediator involved in an immune response. Here the authors show that S100A4 induces production of TNF-α, IL-1 and IL-6 in PBMC via TLR-4 and NFκB dependent pathway and thus may contribute to the pathogenesis of RA.